Inside Unmanned Systems

AUG-SEP 2018

Inside Unmanned Systems provides actionable business intelligence to decision-makers and influencers operating within the global UAS community. Features include analysis of key technologies, policy/regulatory developments and new product design.

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72 unmanned systems
inside
August/September 2018
MARINE INNOVATION
is not on major trade routes, so there
is little incentive to monitor it, other
than scientific endeavors," Bousquet
said. "If we could use low-cost drones
to monitor it, it would be extremely
useful."
Ocean-monitoring robots also can
help with search and rescue missions,
keep an eye on fish stocks, watch pro-
tected areas, and gather data for me-
teorology to, for instance, better model
the track of hurricanes, Bousquet said.
"Understanding and monitoring
ocean garbage is also a very important
task," he noted. "It seems to be having a
very large scale impact on marine life,
and by extension, humans."
BOTH AN AIRCRAFT AND SAILBOAT
Drones currently have limited endur-
ance, ranging from a few hours with
batteries to a few days with gas. One
way to extend their range is to have
them harvest energy from their envi-
ronment, such as from the wind or sun.
A number of high-altitude, long-
endurance solar-powered airplanes
do exist, such as A irbus' Zephy r.
However, "there is barely enough en-
ergy in solar power to sustain f light,"
Bousquet said. As such, to f ly for days,
solar-powered aircraft are typically
severely limited in how much payload
they can carry, or they must be huge
to catch as much sunlight as possible
and therefore are potentially prohibi-
tively expensive.
In contrast, Bousquet's background
is in wind energy. Before his doctoral
research, he worked at Makani, which
is now part of X, the research arm of
Google's parent company Alphabet.
Makani aims to lower the cost of wind-
generated electricity "using tethered
gliders rather than traditional tur-
bines," Bousquet said.
Recently, Bousquet and his col-
leagues investigated the aerodynam-
ics of albatrosses. They focused on
the species known as the wandering
Upcoming tests will see how the UNAv performs when equipped with a sail.
albatross, which is about the size of a
small drone, with a weight of 10 kilo-
grams and a three-meter wingspan.
"It f lies 1,000 or more kilometers
per day, the stronger the w ind the
better," Bousquet said. "A few years
ago, a team of scientists tagged an
albatross with GPS; the bird used a
storm with 100-plus kilometer-per-
hour winds to f ly over 1,000 kilome-
ters in just 10 hours. This is totally
mind-blowing to me."
The researchers found the me-
chanics that enable albatrosses to
cover vast distances while expend-
ing minimal energ y is their ability
to ride in and out of high- and low-
speed layers of air. Specif ically, the
birds can acquire momentum from
higher, faster layers of air to propel
themselves and soar in lower, slower
layers w ithout hav ing to v ir tually
ever f lap their wings.
The scientists then noted the phys-
ics of albatross f light was very similar
to that of sailboat travel. Boats can use
sails to acquire momentum from the
wind and use it to push against slower-
moving water.
Now, Bousquet and his colleagues
have designed UNAv, an unmanned
nautical air-water vehicle, which is "a
wind-powered drone inspired by both
sailboats and albatrosses," he said. "It
can be seen as either a f lying sailboat
or an 'albatross' with an added sail
and keel."
Ultimately, if the robot can harvest
all the energy it needs for f light from
the wind, "there is no need for refuel-
ing, so a robotic albatross could sur-
vey and study the oceans for weeks
or months at a time, traveling tens of
thousands of kilometers in a single
mission," Bousquet said.